<template>
  <div>
    <span v-for="(item, index) in arr" :key="index"
      ><input type="checkbox" :value="item" @click="sum(index, $event)" />{{
        item
      }}
    </span>
    <p>累加值：{{ num }}</p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: [9, 15, 19, 25, 29, 31, 48, 57, 62, 79, 87],
      num: 0,
    };
  },
  methods: {
    sum(index, e) {
      if (e.target.checked) return (this.num += this.arr[index]);
      this.num -= this.arr[index];
    },
  },
  computed: {},
};
</script>
